// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

// This class responds to requests from renderers for the list of plugins, and
// also a proxy object for plugin instances.

#ifndef CONTENT_BROWSER_PLUGIN_SERVICE_IMPL_H_
#define CONTENT_BROWSER_PLUGIN_SERVICE_IMPL_H_

#include "ppapi/features/features.h"

#if !BUILDFLAG(ENABLE_PLUGINS)
#error "Plugins should be enabled"
#endif

#include <map>
#include <memory>
#include <set>
#include <vector>

#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/scoped_vector.h"
#include "base/memory/singleton.h"
#include "base/sequence_checker.h"
#include "base/sequenced_task_runner.h"
#include "base/synchronization/waitable_event_watcher.h"
#include "base/time/time.h"
#include "build/build_config.h"
#include "content/browser/ppapi_plugin_process_host.h"
#include "content/common/content_export.h"
#include "content/public/browser/plugin_service.h"
#include "content/public/common/pepper_plugin_info.h"
#include "ipc/ipc_channel_handle.h"
#include "url/gurl.h"

#if defined(OS_WIN)
#include "base/win/registry.h"
#endif

#if defined(OS_POSIX) && !defined(OS_OPENBSD) && !defined(OS_ANDROID)
#include "base/files/file_path_watcher.h"
#endif

namespace base {
class SingleThreadTaskRunner;
}

namespace content {
class BrowserContext;
class PluginServiceFilter;
class ResourceContext;
struct PepperPluginInfo;

class CONTENT_EXPORT PluginServiceImpl
    : NON_EXPORTED_BASE(public PluginService) {
public:
    // Returns the PluginServiceImpl singleton.
    static PluginServiceImpl* GetInstance();

    // PluginService implementation:
    void Init() override;
    bool GetPluginInfoArray(const GURL& url,
        const std::string& mime_type,
        bool allow_wildcard,
        std::vector<WebPluginInfo>* info,
        std::vector<std::string>* actual_mime_types) override;
    bool GetPluginInfo(int render_process_id,
        int render_frame_id,
        ResourceContext* context,
        const GURL& url,
        const url::Origin& main_frame_origin,
        const std::string& mime_type,
        bool allow_wildcard,
        bool* is_stale,
        WebPluginInfo* info,
        std::string* actual_mime_type) override;
    bool GetPluginInfoByPath(const base::FilePath& plugin_path,
        WebPluginInfo* info) override;
    base::string16 GetPluginDisplayNameByPath(
        const base::FilePath& path) override;
    void GetPlugins(const GetPluginsCallback& callback) override;
    PepperPluginInfo* GetRegisteredPpapiPluginInfo(
        const base::FilePath& plugin_path) override;
    void SetFilter(PluginServiceFilter* filter) override;
    PluginServiceFilter* GetFilter() override;
    bool IsPluginUnstable(const base::FilePath& plugin_path) override;
    void RefreshPlugins() override;
    void RegisterInternalPlugin(const WebPluginInfo& info,
        bool add_at_beginning) override;
    void UnregisterInternalPlugin(const base::FilePath& path) override;
    void GetInternalPlugins(std::vector<WebPluginInfo>* plugins) override;
    bool PpapiDevChannelSupported(BrowserContext* browser_context,
        const GURL& document_url) override;

    // Returns the plugin process host corresponding to the plugin process that
    // has been started by this service. This will start a process to host the
    // 'plugin_path' if needed. If the process fails to start, the return value
    // is NULL. Must be called on the IO thread.
    PpapiPluginProcessHost* FindOrStartPpapiPluginProcess(
        int render_process_id,
        const base::FilePath& plugin_path,
        const base::FilePath& profile_data_directory);
    PpapiPluginProcessHost* FindOrStartPpapiBrokerProcess(
        int render_process_id, const base::FilePath& plugin_path);

    // Opens a channel to a plugin process for the given mime type, starting
    // a new plugin process if necessary.  This must be called on the IO thread
    // or else a deadlock can occur.
    void OpenChannelToPpapiPlugin(int render_process_id,
        const base::FilePath& plugin_path,
        const base::FilePath& profile_data_directory,
        PpapiPluginProcessHost::PluginClient* client);
    void OpenChannelToPpapiBroker(int render_process_id,
        const base::FilePath& path,
        PpapiPluginProcessHost::BrokerClient* client);

    // Used to monitor plugin stability.
    void RegisterPluginCrash(const base::FilePath& plugin_path);

private:
    friend struct base::DefaultSingletonTraits<PluginServiceImpl>;

    // Creates the PluginServiceImpl object, but doesn't actually build the plugin
    // list yet.  It's generated lazily.
    PluginServiceImpl();
    ~PluginServiceImpl() override;

#if defined(OS_WIN)
    void OnKeyChanged(base::win::RegKey* key);
#endif

    // Returns the plugin process host corresponding to the plugin process that
    // has been started by this service. Returns NULL if no process has been
    // started.
    PpapiPluginProcessHost* FindPpapiPluginProcess(
        const base::FilePath& plugin_path,
        const base::FilePath& profile_data_directory);
    PpapiPluginProcessHost* FindPpapiBrokerProcess(
        const base::FilePath& broker_path);

    void RegisterPepperPlugins();

    // Run on the blocking pool to load the plugins synchronously.
    void GetPluginsInternal(base::SingleThreadTaskRunner* target_task_runner,
        const GetPluginsCallback& callback);

    std::vector<PepperPluginInfo> ppapi_plugins_;

    // Weak pointer; outlives us.
    PluginServiceFilter* filter_;

    // Used to load plugins from disk.
    scoped_refptr<base::SequencedTaskRunner> plugin_list_task_runner_;

    // Used to verify that loading plugins from disk is done sequentially.
    base::SequenceChecker plugin_list_sequence_checker_;

    // Used to detect if a given plugin is crashing over and over.
    std::map<base::FilePath, std::vector<base::Time>> crash_times_;

    DISALLOW_COPY_AND_ASSIGN(PluginServiceImpl);
};

} // namespace content

#endif // CONTENT_BROWSER_PLUGIN_SERVICE_IMPL_H_
